Gear transmissions having pairs of helical gears mounted on a drive shaft for engagement with respective pairs of helical gears mounted on a driven shaft resulting in even load sharing amongst gears are disclosed in copending U.S. patent application Ser. No. 09/167,760 filed Oct. 7, 1998 which is a continuation application under 35 U.S.C. .sctn.120 of pending application Ser. No. 09/021,622 filed Feb. 9, 1998, both of the preceding applications being entitled IMPROVEMENTS IN POWER SHARING GEAR SETS. The disclosures, including the disclosures of the specification and drawings of prior U.S. patent application Ser. No. 09/167,760 filed Oct. 7, 1998 and Ser. No. 09/021,622 filed Feb. 9, 1998 are hereby expressly incorporated by reference into this present application.
Paired helical gearing permits, as a practical matter, power sharing among multiple gears on a single shaft. Prior to the invention of paired helical gearing, very precise tolerances were required to successfully construct a transmission which had multiple gears on a common shaft. Therefore, prior to the invention of paired helical gearing, transmissions with multiple gears on a single shaft were for most purposes commercially impractical.
A major commercial application for paired helical gearing is transmissions that have constraints on the size of the diameter of gears due to space limitations, but which are also required to transmit significant power.
The present invention is directed to the use of paired helical gearing to provide for multi-speed transmissions suitable for automotive use. In the present application, transmissions for automotive use includes within its meaning, but is not limited to, uses in automobiles, trucks, farm equipment, earth moving equipment, ships, boats and the like.